An evaluation and comparison of drip and conventional furrow irrigation methods on maize

A field study was conducted over two years on maize at Islam Abad Research Station at 34°7′42′′N and 46°27′23′′E and elevation of 1348 m a.s.l in Kermanshah Province, western Iran in order to compare the effects of different irrigation methods and treatments on irrigation water use efficiency, crop yield, yield response factor, pan and seasonal crop coefficients, and other maize parameters. The experiment was a complete randomized block design with three replicates. During the study, irrigation water was applied at 40, 60, 80 and 100% of the maize seasonal water requirement for different surface drip tape (SDT) treatments, and 100% only for conventional furrow irrigation treatments with and without soil and water monitoring. The results showed that by using the above-mentioned different drip tape and surface treatments with soil and water monitoring, maize seasonal irrigation water use savings of 81, 71, 61, 52 and 36% were achieved compared with local conventional furrow irrigation without any soil, water and root monitoring, respectively. The yield response factor (K _y), seasonal crop (K _c) and pan coefficient (K _p) for maize were 0.80, 0.76 and 0.97, respectively.     

Bioinsecticide production by the bacterium Bacillus thuringiensis. 1. Pattern of cell growth,toxin production and by-product synthesis

To develop a cost-effective process for the production of Bacillus thuringiensis-based insecticide, it is important to cultivate the bacterial strain in rich medium to obtain the highest yields of spore-crystal complexes. It was found that cultivation of the bacterium in medium with high concentrations of glucose (50–90 g l^?1) resulted in much lower bacterial spores, crystal protein and lower toxicity, when tested against Spodoptera littoralis and Anagasta kuehniella larvae. The best results were obtained with glucose concentration of 20.0 g 1^?1 as 7.1 × 10¹¹ spores ml^?1 and 3.4 g l^?1 of crystal protein were achieved with LC₅₀ of 40.1 and 50.2 mg kg^?1 meal against S. littoralis and A. kuehniella, respectively. However, >21% of the consumed glucose was diverted into by-product synthesis at the expense of spore-crystal protein mixture. Only 78.3% of consumed glucose was converted into spores and crystal protein. Among by-products formed, acetic acid and β-hydroxybutyric acid (PHB) were produced during the phase of active growth and glutamic acid and succinic acid during the phase of active toxin production.     

Entomopathogenic fungi and plant essential oils are not compatible in controlling Tribolium castaneum (Herbst)

Journal of Plant Diseases and Protection - Entomopathogenic fungi (EPF) and essential oils (EOs) can show either positive or negative interactions when used for controlling insect pests. First, the...     

Spatial variability of bulk soil electrical conductivity in a Malaysian paddy field: key to soil management

On-the-go EC sensor is a useful tool in mapping the apparent soil electrical conductivity (EC_a) to identify areas of contrasting soil properties. In non-saline soils, EC_a is a substitute measurement for soil texture. It is directly related to both water holding capacity and cation exchange capacity (CEC), which are key ingredients of productivity. This sensor measures the EC_a across a field quickly and gives detailed soil features (1-s interval) with few operators. Hence, a dense sampling is possible and therefore a high resolution EC_a map can be produced. This paper presents experiences in acquiring detailed EC_a information that is correlated to other soil properties for precision farming of rice. The study was conducted on a 9 ha rice plot in MARDI Seberang Prai Station, Penang. The VerisEC3100 was pulled across the field in a series of parallel transects spaced about 15 m apart. The study showed that shallow and deep EC_a had high correlation and shallow EC_a had significant correlation to P. Deep EC_a had significant correlation to P, K and yield. Regression equations showed that N and P could be estimated by shallow EC_a but, pH, K and yield were better estimated by deep EC_a. This study was able to draw some basic ideas of nutrient zone management according to precision farming technique.     

Ascorbic Acid Enhances Growth and Yield of Sweet Peppers (Capsicum annum) by Mitigating Salinity Stress

Salinity is a crucial problem which has affected crop productivity globally. Ascorbic acid is considered helpful against abiotic stresses due to its powerful antioxidant potential. In the pot experiment, salinity stress (0, 35, 70, and 105?mM) was applied to sweet peppers in split doses after 20 days of transplantation. To mitigate the adverse effects of salinity, ascorbic acid (0, 0.40, 0.80, and 1.20?mM) was applied as foliar spray after a 6-day interval during vegetative growth. Sweet pepper plants sprayed with distilled water (control) recorded maximum plant height (cm), leaf area (cm²), number of branches, stem diameter (mm), number of fruit plant^?1, fruit diameter (cm), yield plant^?1 (g), and chlorophyll content (mg 100?g^?1), while the maximum polyphenol oxidase (PPO) activity (unit mg protein^?1 min^?1) and ascorbate peroxidase (APX) activity (unit mg protein^?1 min^?1) were recorded in plants treated with 70?mM NaCl application. Salinity stress beyond 70?mM significantly reduced all the studied parameters. An ascorbic acid concentration of 1.20?mM significantly mitigated the negative effects of salt stress and recorded maximum plant height (cm), number of leaves plant^?1, leaf area (cm²), number of branches plant^?1, stem diameter (mm), number of fruit plant^?1, fruit diameter (cm), yield plant^?1 (g), chlorophyll content (mg 100?g^?1), PPO activity (unit mg protein^?1 min^?1), and APX activity (unit mg protein^?1 min^?1). Hence, a 1.20?mM concentration of foliar ascorbic acid could be used in saline conditions up to 70?mM of sodium chloride (NaCl) for better growth, productivity, and enzymatic activity of sweet peppers.

     

Inhibitory effects of Sage extract on the growth of enteric bacteria

Antibacterial activity of Sage extract at concentrations of 0.1, 0.05, 0.025, 0.0125, 0.00625, 0.003125, 0.00156, 0.0005 and 0.00025 g dL(-1) against Salmonella typhi, Shigella sonnei, S. flexneri, Proteus vulgaris, Staphylococcus aureus, ETEC Escherichia coli and Pseudomonas aeruginosa was evaluated. Susceptibility testing of bacterial strains against 18 antibiotics was also performed for comparison. The results showed that P. aeruginosa and ETEC E. coli were completely resistant to Sage extract even at concentration of 0.1 g dL(-1). Its antibacterial activity (0.1 g dL(-1)) against P. vulgaris, S. flexneri and S. sonnei was the same as nitrofurantoin and ampicilline respectively. Sage extract (0.1 and 0.05 g dL(-1)) exhibited the same effects as ampicilline and streptomycin against S. typhi. Its antibacterial activity (0.1, 0.05 and 0.25 g dL(-1)) against S. aureus was the same as ceftazidim, chloramphenicol, gentamycin, neomycin and nitrofurantoin and was more significant compared to streptomycin and vancomycin. The results suggest Sage can be considered as an alternative herbal in the treatment of infections caused by the above-mentioned bacteria.     

Fish meal replacement with rice protein concentrate in a practical diet for the Pacific white shrimp, Litopenaeus vannamei Boone, 1931

Replacement of fish meal (FM) with rice protein concentrate (RPC) as a practical diet for the Pacific white shrimp, Litopenaeus vannamei, was evaluated. Five isonitrogenous (36.6% protein) diets, formulated by replacing 0, 25, 50, 75, and 100% of FM by RPC, were fed to shrimp (initial weight of 6.99 ± 0.08 g) five times daily to satiation for 60 days. Relatively high final weight (FW 17.64–18.25 g) and weight gain (WG 10.81–11.39 g) were obtained in treatments up to 50% of the plant protein inclusion. Above this inclusion level, FW (14.93–14.35 g) and WG (7.68–7.23 g) were reduced. Survival was high (≥95%) and similar for all diets. There were no significant differences (P > 0.05) in tail-muscle composition (moisture, protein, lipid, and ash) among different dietary treatments. Dispensable and indispensable amino acids of the tail muscle of shrimp fed with 25, 50, and 75% RPC were significantly higher than the FM (0%) and 100% RPC diets. A decreasing trend in apparent digestibility coefficient (excluding dry matter) for crude protein (90.52–52.41), ether extract (94.11–80.03), organic matter (87.25–50.16), and gross energy (89.41–55.24) was observed at higher RPC inclusion rates. The results suggest that RPC meal can be a potential candidate for FM replacement up to 50% of the protein in shrimp diets.     

A spatial analysis of land cover patterns and its implications for urban avifauna persistence under climate change

Context

Although biodiversity in cities is essential to ensure the healthy functioning of ecosystems and biosecurity over time, biodiversity loss resulting from human interventions in land cover patterns is widespread in urban landscapes. In the Southern Hemisphere, climate change is likely to accelerate the process of landscape upheavals, and consequently biodiversity loss.

Objectives & Methods

The aim of this research is to test the potentials of landscape pattern composition and configuration in safeguarding indigenous avifauna against the local impacts of climate change in urban landscapes, with reference to New Zealand. To build up a platform for landscape pattern interpretation, the literature was reviewed and semi-structured interviews with six subject-matter experts were conducted to provide information about the most important avifauna in the study area, key information on their ecological traits and niches, possible impacts of climate change on their primary habitats, and spatial requirements for ongoing species survival as the climate continues to change. A spatial analysis of land cover patterns was undertaken in Wellington, New Zealand using GIS and FRAGSTATS.

Results

Although there are still opportunities for biodiversity conservation in the study area, the current land cover patterns are unlikely to safeguard the selected species against climate change impacts.

Conclusions

Eight implications for avifauna persistence under climate change are discussed for the first time in relation to a New Zealand context. These implications can give rise to a higher level of informed decision-making on a wide range of practices for biodiversity conservation related to uncertainties associated with climate change.

     

Development of Rose Bengal test against mallein test for rapid diagnosis of equine glanders

Tropical Animal Health and Production - Burkholderia mallei, the etiologic agent of the disease known as glanders. Clinical and bacteriological diagnosis of glanders is difficult in the early...